{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,11]],"date-time":"2026-09-11T05:06:39Z","timestamp":1789103199791,"version":"build-2803163510"},"reference-count":36,"publisher":"MDPI AG","issue":"9","license":[{"start":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T00:00:00Z","timestamp":1788912000000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"U.S. National Institutes of Healthh","award":["R01ES021446"],"award-info":[{"award-number":["R01ES021446"]}]},{"name":"U.S. National Institutes of Healthh","award":["R01-ES007821"],"award-info":[{"award-number":["R01-ES007821"]}]},{"DOI":"10.13039\/100000066","name":"National Institute of Environmental Health Sciences","doi-asserted-by":"crossref","award":["P01ES022844"],"award-info":[{"award-number":["P01ES022844"]}],"id":[{"id":"10.13039\/100000066","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/100000066","name":"National Institute of Environmental Health Sciences","doi-asserted-by":"crossref","award":["RD83543601"],"award-info":[{"award-number":["RD83543601"]}],"id":[{"id":"10.13039\/100000066","id-type":"DOI","asserted-by":"crossref"}]},{"award":["P01ES022844"],"award-info":[{"award-number":["P01ES022844"]}],"id":[{"id":"https:\/\/ror.org\/00j4k1h63","id-type":"ROR","asserted-by":"publisher"}]},{"award":["RD83543601"],"award-info":[{"award-number":["RD83543601"]}],"id":[{"id":"https:\/\/ror.org\/00j4k1h63","id-type":"ROR","asserted-by":"publisher"}]},{"DOI":"10.13039\/100000066","name":"NIEHS","doi-asserted-by":"crossref","award":["P42-ES005947"],"award-info":[{"award-number":["P42-ES005947"]}],"id":[{"id":"10.13039\/100000066","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/100000066","name":"NIEHS","doi-asserted-by":"crossref","award":["P20ES018171"],"award-info":[{"award-number":["P20ES018171"]}],"id":[{"id":"10.13039\/100000066","id-type":"DOI","asserted-by":"crossref"}]},{"DOI":"10.13039\/100000066","name":"NIEHS","doi-asserted-by":"crossref","award":["P30ES017885"],"award-info":[{"award-number":["P30ES017885"]}],"id":[{"id":"10.13039\/100000066","id-type":"DOI","asserted-by":"crossref"}]},{"name":"National Institute of Public Health\/Ministry of Health of Mexico"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Toxics"],"abstract":"<jats:p>Evidence is accumulating linking prenatal fluoride exposure with adverse neurodevelopment. Maternal urinary fluoride (MUF) is a well-established biomarker of fluoride exposure. Because most fluoride is stored in calcified tissues, pregnancy-associated changes in bone metabolism may contribute to fetal fluoride exposure. We evaluated whether maternal bone resorption, indexed by urinary N-telopeptide of type I collagen (NTX), is associated with MUF across pregnancy. Participants were drawn from the Early Life Exposures in Mexico to Environmental Toxicants (ELEMENT) birth cohorts. Each woman contributed one paired MUF\u2013NTX measurement per trimester. Both biomarkers were creatinine-normalized to account for urine dilution. Trimester-specific generalized linear models with a Gamma distribution estimated associations between NTX and MUF, adjusting for maternal age, birth order, infant birthweight, and cohort. Across the trimesters, MUF was relatively stable (0.89 \u00b1 0.37, 0.91 \u00b1 0.41, and 0.83 \u00b1 0.42 mg\/L), whereas NTX increased with gestation (68.0 \u00b1 33.5, 99.0 \u00b1 50.3, and 132.4 \u00b1 65.4 nmol BCE\/mM creatinine). Higher NTX was consistently associated with higher MUF: \u03b2 = 0.00315 (p &lt; 0.0001) in Trimester 1, \u03b2 = 0.00207 (p = 0.001) in Trimester 2, and \u03b2 = 0.00253 (p &lt; 0.0001) in Trimester 3, corresponding to 11%, 11%, and 18% higher MUF per 1-SD increase in NTX. Results were unchanged after adjustment for estimated fluoride intake, with no evidence of non-linearity. Maternal bone resorption was independently associated with MUF, consistent with a skeletal contribution to urinary fluoride. Research may be needed on measures that can blunt bone mobilization of fluoride during pregnancy.<\/jats:p>","DOI":"10.3390\/toxics14090798","type":"journal-article","created":{"date-parts":[[2026,9,9]],"date-time":"2026-09-09T10:19:16Z","timestamp":1788949156000},"page":"798","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Association of Maternal Bone Resorption with Urinary Fluoride Levels During Pregnancy"],"prefix":"10.3390","volume":"14","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5574-0087","authenticated-orcid":false,"given":"Morteza","family":"Bashash","sequence":"first","affiliation":[{"name":"Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-0471-1427","authenticated-orcid":false,"given":"Karen E.","family":"Peterson","sequence":"additional","affiliation":[{"name":"Department of Nutritional Sciences, University of Michigan School of Public Health, Ann Arbor, MI 48109, USA"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"investigation","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5389-0209","authenticated-orcid":false,"given":"E. Angeles","family":"Martinez-Mier","sequence":"additional","affiliation":[{"name":"Department of Dental Public Health and Dental Informatics, Indiana University School of Dentistry, Indianapolis, IN 46202, USA"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8775-8399","authenticated-orcid":false,"given":"H\u00e9ctor","family":"Lamadrid-Figueroa","sequence":"additional","affiliation":[{"name":"Department of Perinatal Health, Instituto Nacional de Salud P\u00fablica, Cuernavaca 62100, Morelos, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3957-0970","authenticated-orcid":false,"given":"\u00c1ngel","family":"Santiago","sequence":"additional","affiliation":[{"name":"Department of Perinatal Health, Instituto Nacional de Salud P\u00fablica, Cuernavaca 62100, Morelos, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"methodology","vocabulary":"credit"},{"role":"software","vocabulary":"credit"},{"role":"validation","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"visualization","vocabulary":"credit"}]},{"given":"Adrienne S.","family":"Ettinger","sequence":"additional","affiliation":[{"name":"Rutgers Health, Rutgers University, Newark, NJ 07107, USA"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3322-3334","authenticated-orcid":false,"given":"Martha Mar\u00eda","family":"T\u00e9llez-Rojo","sequence":"additional","affiliation":[{"name":"Center for Nutrition and Health Research, Instituto Nacional de Salud P\u00fablica, Cuernavaca 62100, Morelos, Mexico"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3676-2707","authenticated-orcid":false,"given":"Howard","family":"Hu","sequence":"additional","affiliation":[{"name":"Department of Population and Public Health Sciences, Keck School of Medicine, University of Southern California, Los Angeles, CA 90033, USA"}],"role":[{"vocabulary":"crossref","role":"author"},{"role":"conceptualization","vocabulary":"credit"},{"role":"methodology","vocabulary":"credit"},{"role":"writing-review-editing","vocabulary":"credit"},{"role":"funding-acquisition","vocabulary":"credit"},{"role":"supervision","vocabulary":"credit"},{"role":"resources","vocabulary":"credit"},{"role":"data-curation","vocabulary":"credit"},{"role":"writing-original-draft","vocabulary":"credit"},{"role":"project-administration","vocabulary":"credit"},{"role":"formal-analysis","vocabulary":"credit"}]}],"member":"1968","published-online":{"date-parts":[[2026,9,9]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"097017","DOI":"10.1289\/EHP655","article-title":"Prenatal Fluoride Exposure and Cognitive Outcomes in Children at 4 and 6\u201312 Years of Age in Mexico","volume":"125","author":"Bashash","year":"2017","journal-title":"Environ. 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